Paulyy

https://www.bremershifters.com/

So these have been on the talks on facebook. Shown at SEMA.
A device that turns your manual box into a sequential shifting box.

Now i was looking at the movement of the output of the box and it looks like it may be possible to rig up to our transaxles.

If you convert your gearbox into a straight cut gears (dog box) and with the bremer shifter, you essentially have a sequential box. This would be great for people who have restrictions on what gearbox you're allowed to use in motorsport events. I.e me.

Fell free to discuss.

333pg333

http://www.sqsracing.com/produkt/277...porsche-ultima

Assuming it's something along these lines. Doesn't show anything but the shifter from what I can see on the Bremer site? Still would have to get some Dog gears cut. Tons cheaper than the full SQ gearbox. Be interesting if they can 'sneak' this through to Clubsprint. Bet a few try.

333pg333

http://www.s1sequential.com/
Another version. Looks like both brands are a bit different from the SQS product as there is no provision for a Transaxle layout.

ealoken

I hope this is bether than the Ikeya seq ****fter was for my old Skyline R32.

Paulyy

I thought i could use this in club sprint. I assumed the rules said that you're not allowed to use a sequential gearbox. But you can use any gearbox as long as long as that perticular style (manual, auto, sq) came as OEM

951and944S

Cool stuff, it's all mechanical, so I like it.

Years ago when working on a GT (open here) class car for myself, an electronics geek friend of mine from Ireland (his moniker everywhere is 'Gadgetboy'.. ) was working on a setup where the shifter itself was just a stick and a logics board which signaled two motors on different axis' at the rear.

Project fell by the wayside.

This setup kept the clutch pedal function but could have been taken further with internal gearbox changes.

The thing is, there is an exponential lesser gain to be had the better you are at heel/toe.

I doubt a sequential system would benefit my son's lap times by more than 1/2 a second average at the tracks we do even though the class I am moving him to with new 944S lightweight allows for "gears are free".

This is a stock 944 gearbox with stock clutch and stock weight flywheel, no gimmicks.

Skip to 13:00 where the action for the lead is -
T

333pg333

I'd assume most of us can shift that quickly Mr T. The biggest advantage of an SQ trans is the upshift rather than the 'heel/toe' downshift. More so with a big turbo. Keeps the turbo spooled much more than even a well shifted H pattern box. We have some back to back data of our car against the previous WTAC winner in Pro Class and the differences in shift times were in .10's of a second per shift. Dozen shifts per lap etc.... Add to that the spool differences...it's a clear advantage with an SQ box. Problem is to convert a 944/68 to one, you have to allow circa $50k unless you can do all the cutting and fabbing yourself. For the average Joe who would have to get a competent shop to do this, there are many hours involved. It's a shame as it's one thing I would like to do in the future. Motor issues pending.

951and944S

Yeah, I meant the downshifts. Can most people shift that quickly on downs...., hardly.

I get where you're coming from on the boost staying up, that's why here, most turbo cars are autos.

And I agree, there's time to be had on the ups, especially in your configuration (and the competition) and it's probably at least what you say, (1/10 or more).
So we are talking about a second around the track you guys did the WTAC on...., close enough, and that is easily the difference between 1st and 2nd....agreed.

Let me ask you though....., what is the guy that drives your car when you are not behind the wheel worth vs you..?

Is it a second...?

Two...?

And Paulyy, who I'm guessing is looking to get into this format. Do you you think he can go at it for a year's worth of practice days and there's not a driver who can jump in his car and go 2 seconds faster...?

Then there's the variance between laps even with your assumed best driver.

There's that one lap on the same day, same conditions where you stand at trackside and say "d@mned", where'd he pull that one from...?

Hit everything just right, didn't make any mistakes.

What I'm getting at is, the difference in fast lap variance, considering all other possibilities is well inside the maximum benefit of 1/10nth per upshift.

That's why I dropped it.

Surely not worth $50k.

For $10K you could hire Leah Keen to fly over and drive your car 2-3 seconds faster over a lap....

More for us than what y'all do because it's so easy to lose a second or two being balked while making a pass or just traffic in general which make a 1/10nth per shift gain even more moot.

On another note...., are y'all at least using "flat shift" feature with your ECU...?

T

951and944S

By the way, the avenue you guys should be exploring is the PDK.

I said it a few times before (Max and TonyG).

With a data streaming scan tool, I can drive and auto and tell you what the ratio change "time to complete" is on an auto.

Anything outside that preprogrammed allowance for a shift to "complete" sets a service light on GM, Ford, etc.

It's less than .5/sec. In that, you have a clutch that has to exhaust it's piston apply pressure and in the case of some boxes, a band has to apply via a servo piston and pin and completely stop a housing that is spinning at 5k rpm.

With the type of manual box shifting you guys are talking about, there is the time interval that a slider has to decouple 3rd (ex) and slide to engage 4th.

It's minimal and equal to or less than an auto but it is not as quick as the PDK which is already in the next gear before it is ever requested because it uses two input shafts, one inside the other (thus the name Double Koupling).

Here in the USA, on an insurance auction site, you can buy a complete totaled Cayman for as little as $1k.

I don't see it as impossible to have an aftermarket ECU mimic the inputs/output data that the transmission would require even if it took a $10k software to be written.
Not to mention running the Cayman ECU and harness piggyback with what you are running now.

This is where I'd be going.

You could buy 2 cars for $5k and have a plug in back up transmission that is faster shifting that what Duke and Rod use unless I see data that conflicts with what I am saying.

T

333pg333

That's good Tech info T.

Your Son is a good peddler but I'd say that most competent racers can heel / toe to a similar skill level. Especially on an n/a car with more alacrity underfoot than the traditionally more 'doughy' turbo cars as such. Be interesting to follow his progress once he gets out of the 944 n/a world though.

The differences in upshifts were more in the vicinity of .3 of a second from memory. So we calculated approx 2 secs around SMP (Sydney Motorsport Park) give or take. To spend money on e.g. power to gain 2 seconds can be an expensive business. (ask me how) So 2 secs is a big carrot to dangle. We were able to easily find that with our first real foray into Aero for a lot less dollars too. Obviously it becomes a case of diminishing returns the faster and further you go down a particular path. We can update our Aero and possibly gain another 1-2 seconds. This was my intention but the best laid plans etc...

951and944S

The best feedback suggests that the PDK completes a ratio change in .040/sec. The guys that switched from Cups with sequential straight cut gear boxes to the Cayman class in PCA racing say it's not even a contest. To put that in context, that's 25 shifts = 1.00 second.
Why don't you research what it'd take to control the transmission, the physical mounting is just custom fabrication, it's emulating the requirements of the TCU that's gonna be ground breaking, vehicle speed, 4 x wheel speed, throttle position, engine load, etc.
If you need somebody on the ground (if USA source for a donor is cheaper), I'll help you out. Once you have it all configured and a trans takes a dump, all you need is another $1-5k totaled car donor for a replacement.

LOL, I'm a good peddler, as good as anybody I've been around.
Can't touch him though and his car is full throw with not even a short shifter...
I mentioned in your engine thread about keeping a US based car stationed/stored for you to fly over and race.
It's WAY cheaper. I have a buddy with a pretty competitive NA 944 for sale for $6k with spares. Max has a 2 bay garage at a semi-local track that can store it for $100 per month and it's already at a track....arrive and drive.
Max and I can even get a race credential waiver.
In either event, if you were interested (not necessarily in buying the car) I'd be willing to offer an invitation for a one off, fly in, race, fly out at a better track like the yearly NOLA PCA race and I'm sure that between me and Max, we could scratch you up a top running 944 class car.
And yes, it's generous...., but I have a motive....

T

Paulyy

I like your idea on the PDK box. I wonder how it'll play in the rules for me.
It's considered an auto right?
Since my 924 is actually an Auto chassis, and it is clearly an option for any 924, 944 & 968

This to me seems to fit inside the rules.
Might be onto something here.

My knowledge stops here -
What do you exactly need to control the PDK box? im guessing it's no simple input/output saying shift now
Do they have a control unit from that's separate to the ECU?

If this is viable, it is definitely worth looking into.

951and944S

On other types with +/- up/down auto overridethat I already work on, basically (let's take a 4 speed) there are two shift solenoids A and B (imagine additional C for 6spd).
With two solenoids normally open bleeding circuit pressure, you can get 4 ratio commands by triggering them in a pair combo as A=on B=off, A=on B=on, A=off B=off and A=off B=on.

The "on solenoid" checks the normal bleed and circuit pressure builds to move a spool valve (1-2 shift valve) and so on.

Circuitry-wise, they are already supplied with key on 12V and are activated by applying grnd signal from TCU.

Vehicle sees TPS is within range for an upshift vs vehicle speed, grnd signal command triggers from TCU and shift solenoid A is "on", checks bleed, moves shift valve, circuit opens to apply driving component, either a clutch piston or servo + pin.

So, without even a TCU present, if I apply +12V to energize solenoids and connect a rotary **** which would supply a grnd signal alternately to shift solenoid A & B, I can make it shift 1-2-3-4 with no TCU at all.

I'm sure the PDK is more complicated but I was never required to know how they work.

The TCU comes in by not "allowing" me to go to 1st gear at 90mph using VSS, etc. It "knows" vehicle speed is too high for 1st range.

The PDK will have some built in go vs no go.

It could very well be like F1 transmissions several years back where the driver would come to a 2nd gear corner from 200mph and just blip 7-6-5-4-3-2 way ahead of the corner and when "allowed" (VSS decreasing speed), the trans would blip down to 2nd.

If this is not a factory feature of the PDK, it could certainly be written in software that way.

T

951and944S

A quick search for a Cayman ECU used, in working condition is $345 USD.

T

333pg333

I've thought about PDK before but I'd say there'd be a question over how much tq they can handle?
I'd certainly doubt that the Caymen box would hold 600ft/lbs to the wheels or thereabouts. Having said that, perhaps it or parts thereof, could be improved. It's certainly an interesting idea.

Even though it 'might' be considered an Automatic, it still would be considered Paddle Shift which isn't allowed in my class. Not sure about Clubsprint though as some new cars must come with a similar setup. Although they don't allow a lot of high end sports cars enter in that class anyway. Pauly, are there any cars in Clubsprint that can run Paddle?

T, flying over and racing in the US would definitely be cheaper than what I've been paying over the years...by a Loooooooooong margin. Just nothing I'd ever considered. Thanks for the thought though. :-)